Best Practices for Video Ads

This guide outlines some best practices for implementing in-stream ads.

Creative review process

Video ads must pass Ad Exchange's standard verification checks before they are served by Real-Time Bidding (RTB). After Ad Exchange approves them, RTB starts and continues to serve them until they are disapproved by Ad Exchange.

Note that video tags should remain live for the entire duration of the review. If the video tags are not live or become stale for any reason, they may be disapproved, post-filtered, and/or throttled.

Key performance metrics

Ad Exchange uses the following metrics to measure video ad health. It’s important to understand what these mean when assessing performance issues like latency and filtering.

  • View rate
    For video ads, view rate is the rate at which an ad is correctly served and rendered.
    View rate = Number of times the first frame is rendered / Number of times the ad won an auction
  • Error rate
    Common errors include:
    • Corrupted media file
    • File not found
    • Malformed VAST
    • Timeout
    Error rate = Number of errors / Number of won impressions
  • Dropoff rate
    The percentage of won auctions that don't get viewed because of user action or publisher player error.
  • Abandonment rate
    The percentage of users who start to view a video ad but do not finish viewing the ad—for example, they navigate away from the site or close the browser. A high abandonment rate is reflective of poor audience reception, due to low quality video ads or incorrect audience targeting.
  • Skip rate
    The percentage of users who skip viewing a video ad.

Note that:

View rate + dropoff rate + error rate = 100%

And for:

  • Skippables ads
    View rate + skip rate + abandonment rate = 100%
  • Standard in-stream ads
    View rate + abandonment rate = 100%

Video ad throttling

Video ad throttling prevents problematic video ads with low view rates and high error rates from competing in the auction. Ad Exchange uses view rate and error rate to determine how well a video ad is being served. Ad Exchange throttles a video ad by limiting the total number of auctions it can win per hour to twelve.

Why is throttling used?

Video ad throttling helps keep the exchange running smoothly because even if a buyer wins an impression but the buyer's video ad is not shown, the buyer is not charged for the impression. Ad Exchange's video ad throttling ensures that video ads with fewer errors and higher view rates serve more often than problematic video ads, which benefits both publishers and buyers.

Reduce throttling

To ensure that a video ad is not throttled, make sure the video tag is functional and is not returning errors. Check the Filtered Bids section in the Bidding tab of your RTB Dashboard. Look for the video creative "throttled" reason listed in the Google filtered bids section. Click Details to see a breakdown by creative ID or publisher domain.

Video ad filtering

Video ads must meet the video ad slot requirements passed in the bid request. When a buyer responds to a video bid request with a video tag that does not meet those requirements, the buyer's response is filtered. For example, if a bid request requires a skippable video and a buyer responds with a non-skippable video ad, that response will be filtered from the auction because the video ad is ineligible to serve in the publisher player. Ad Exchange honors publisher settings to foster good user experience.

Why are video ads filtered?

To find out why a video ad is filtered, look up the creative status codes dictionary file for the filtering reasons. For example, video ads can be filtered for the these reasons:

  • Missing MP4 video file
  • Ad duration longer than requested
  • Ad duration shorter than requested
  • Skippable ad on a non-skippable request
  • Non-skippable ad on a skippable request

Reduce filtering

To reduce filtering of video ads:

  • Make sure your bidder is paying attention to the video portion of the bid request and responds with only ads that match the request.
  • Check the Filtered Bids section in the Bidding tab of your RTB Dashboard. Look for the video creative "filtered" reason listed in the Google filtered bids section. Click Details to see a breakdown by creative ID or publisher domain.

Ensure delivery

The following guidelines help buyers to ensure smooth delivery of their video ads:

  • In-stream video ad technical specifications
    To be eligible to serve on all types of inventory, video tags must contain the MP4 MIME type. If the MIME type is missing, the video ads can be filtered, throttled, or both.
  • Skippable compliance
    Make sure your 15s or 30s skippable ads have the skip offset after 5 seconds. There are three types of inventory: allow skippable, require skippable, and block skippable; so make sure your bidder is reading the SkippableBidRequestType enum and responding accordingly.
  • Duration compliance
    Bidders should read the minimum and maximum ad duration fields and respond accordingly.
  • HTML5 compliance
    YouTube, one of our largest publishers, has been transitioning desktop traffic from Flash video player to HTML5 video player. This means VAST creatives now require HTML5 media assets (MP4) to be eligible to run on YouTube. Hence, you should run HTML5 compliant creatives.
  • SSL
    On desktop, many publishers use SSL for logged-in users, which means that a very valuable set of users is now only accessible with SSL creatives. Thus buyers should have at least some SSL compliant creatives.
  • Targeting specific YouTube channels
    Ad Exchange allows buyers to target specific YouTube channels. Talk to your Account Manager for more information on how to target the latest available inventory.

Troubleshooting resources

To ensure your video campaigns run smoothly:

  1. Make sure your video creatives comply with the Ad Exchange technical specifications.
  2. Check your pretargeting setup to make sure it is configured for the type of inventory you want to receive.
  3. After your campaigns are live, check that all creatives are approved and are functioning properly. Use the following resources to troubleshoot any filtered or throttled video ads:

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